NEHRP Clearinghouse
- Title
- Dynamic Analysis of Multiply Tuned and Arbitrarily Supported Secondary Systems.
- File
- PB84118272.pdf
- Author(s)
- Igusa, T.; Der Kiureghian, A.
- Source
- National Science Foundation, Washington, DC., July 1983, 240 p.
- Identifying Number(s)
- UCB/EERC-83/07
- Abstract
- The objective of this study is to include all of the important and complicated dynamic characteristics in a dynamic analysis of linear, multi-degree-of-freedom (MDOF) secondary subsystems with multiple support points attached to linear MODF primary subsystems. These characteristics include: interaction between the two subsystems; cross-correlations between motions of the support points and modal responses for stochastic input; resonance or tuning phenomena when a set of frequencies of one system is tuned with one or more frequencies of the other system; and non-classical damping effects when the damping ratio of the two subsystems are different. The basic approach of the analysis is to consider the combined primary and secondary subsystems as a single dynamic assemblage. Such an approach implicitly includes the effects of interaction, multiple support motions, resonance, and non-classical damping, but was avoided in the past due to the size and complexity of the resulting eigenvalue problem and the fact that such systems are non-classically damped. The main results of the analysis are applied to several representative example systems and compared with results obtained from numerical analysis.
- Keywords
- Building subsystems; Eigenvalues; Substructures; Damping; Dynamic response; Buildings; Earthquake engineering; Degrees of freedom; Approximation; Frequency response; Perturbation; Earthquakes